what is use of class component in react code example

Example 1: class in react

class App extends Component {
    constructor() {
        super()
        this.state = {
            name: "Sally",
            age: 13
        }
    }
    
    render() {
        return (
            <div>
                <h1>{this.state.name}</h1>
                <h3>{this.state.age} years old</h3>
            </div>
        )    
    }
}

Example 2: create react component class

class MyComponent extends React.Component{
    constructor(props){
        super(props);
    };
    render(){
        return(
            <div>
              <h1>
              	My First React Component!
              </h1>
            </div>
        );
    }
};